NMR Spectroscopy Introduction | Lab Instrumentation and Principle
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In this video we have describe about the application and types of NMR, Instrumentation of NMR, Principle of NMR and Spectrum ( Graph) interpretation of NMR.
Lets discuss in detail, NMR (Nuclear Magnetic Resonance) spectroscopy is an analytical technique used to identify compounds. It is based on the principle that major nuclei of atoms possess magnetic moments and angular momentum and when external magnetic field is applied to them, they arrange themselves in the direction of the magnetic field.
To simplify, let us consider an example of Hydrogen Atom as a magnet which has a north pole and a south pole. If we place that magnet(i.e. Hydrogen Atom) in a magnetic field, then the hydrogen atom will reorient itself in such a way that the north pole will be pointing towards the south pole of magnetic field i.e. reorientation in the direction of the magnetic field.
Similarly, the other atoms also have magnetic moment based on their lone pairs. When they are placed in some external magnetic field, they reorient themselves. This reorientation is termed as α-spin. Now, once the reorientation of the atoms in the direction of magnetic field is accomplished, we provide some energy to the same atom so that the atom reorient themselves into the opposite direction. This spin is termed as β-spin. In this spin, the North pole of the nucleus will be facing the North pole of the magnetic field. Hence, this spin will lead to the arrangement of nucleus against the magnetic field. The energy required for the same task is very less as the energy difference between the α-spin and β-spin is not large. As the energy provided to the nucleus will lead to β-spin, when we remove the energy, the nucleus will relax back to its original state i.e. the α state. When the nucleus returns to its initial state, there would be fluctuation in the magnetic field which is often termed as resonance. This fluctuation would lead to the generation of a pulse/ electric signal in the coil surrounding the sample. This current is detected by the detector of NMR machine, and a peak is generated. For every molecule the height will be different as the energy required by the nucleus of the atoms present in the molecule will be different. This is only about hydrogen atom. Lets discuss about a molecule, what happens in molecule.
Every molecule has different density of electrons and thus, if we target any one nucleus or atom of any of the molecules, it may have a different number of electron surrounding. The electrons may belong to its atom or some other atom of the same molecule. Thus there would be magnetic shielding. This means that when external magnetic field is applied to the given sample, some nucleus (who have higher electron density around) will not orient itself completely. Thus this nucleus will require comparatively less energy for the β-spin than the other atoms.
every molecule will have different peaks generated in the NMR spectroscopy, and thus we can easily identify the molecule.
After that we discussed about graph interpretation, specifically about chemical shift (Upfield & Downfield), peak splitting, peak integration.
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In this video we have describe about the application and types of NMR, Instrumentation of NMR, Principle of NMR and Spectrum ( Graph) interpretation of NMR.
Lets discuss in detail, NMR (Nuclear Magnetic Resonance) spectroscopy is an analytical technique used to identify compounds. It is based on the principle that major nuclei of atoms possess magnetic moments and angular momentum and when external magnetic field is applied to them, they arrange themselves in the direction of the magnetic field.
To simplify, let us consider an example of Hydrogen Atom as a magnet which has a north pole and a south pole. If we place that magnet(i.e. Hydrogen Atom) in a magnetic field, then the hydrogen atom will reorient itself in such a way that the north pole will be pointing towards the south pole of magnetic field i.e. reorientation in the direction of the magnetic field.
Similarly, the other atoms also have magnetic moment based on their lone pairs. When they are placed in some external magnetic field, they reorient themselves. This reorientation is termed as α-spin. Now, once the reorientation of the atoms in the direction of magnetic field is accomplished, we provide some energy to the same atom so that the atom reorient themselves into the opposite direction. This spin is termed as β-spin. In this spin, the North pole of the nucleus will be facing the North pole of the magnetic field. Hence, this spin will lead to the arrangement of nucleus against the magnetic field. The energy required for the same task is very less as the energy difference between the α-spin and β-spin is not large. As the energy provided to the nucleus will lead to β-spin, when we remove the energy, the nucleus will relax back to its original state i.e. the α state. When the nucleus returns to its initial state, there would be fluctuation in the magnetic field which is often termed as resonance. This fluctuation would lead to the generation of a pulse/ electric signal in the coil surrounding the sample. This current is detected by the detector of NMR machine, and a peak is generated. For every molecule the height will be different as the energy required by the nucleus of the atoms present in the molecule will be different. This is only about hydrogen atom. Lets discuss about a molecule, what happens in molecule.
Every molecule has different density of electrons and thus, if we target any one nucleus or atom of any of the molecules, it may have a different number of electron surrounding. The electrons may belong to its atom or some other atom of the same molecule. Thus there would be magnetic shielding. This means that when external magnetic field is applied to the given sample, some nucleus (who have higher electron density around) will not orient itself completely. Thus this nucleus will require comparatively less energy for the β-spin than the other atoms.
every molecule will have different peaks generated in the NMR spectroscopy, and thus we can easily identify the molecule.
After that we discussed about graph interpretation, specifically about chemical shift (Upfield & Downfield), peak splitting, peak integration.
SHARE, SUPPORT and SUBSCRIBE!
Subscribe: @baayo
👋 😃 Connect with me on
LinkedIn 👉🏼 - LinkedIn: artirani
Instagram 👉🏼- Instagram: baayo_official
Telegram 👉🏼- https://t.me/baayo_channel
Related Videos:
HPLC Chromatography: HPLC Chromatography Basics Explained
Mass Spectometry : Mass Spectrometry | Principle and Ins...
UV Visible Spectroscopy : UV Visible Spectroscopy | Basic Princ...
6 سال پیش
در تاریخ 1397/09/13 منتشر شده
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